X linked mental retardation
Imen Rejeb1, Lamia Ben Jemaa, Habiba Chaabouni
1Laboratoire de Génétique Humaine, Faculté de Médecine de Tunis, Tunisie.
Background:
Mental retardation (MR) is a group of heterogeneous clinical conditions. There are more than 900 genetic disorders associated with MR and it affects around 3% of the general population. Many MR conditions described are syndromic, fragile X syndrome being the most common clinical entity among them. X linked mental retardation (XLMR) is subdivided in two categories: syndromic XLMR (MRXS) when MR is associated with clinical features and non-syndromic XLMR (MRX) when MR is isolated.
Aim:
The aim of this systematic review of the literature was to join together the results of several studies related to X linked mental retardation and to present various genes implicated in this disease. In this review, focus has been given on genes implicated in mental retardation, the clinical data and on phenotype-genotype correlations.
Methods:
An exhaustive electronic and library research of the recent literature was carried out on the Web sites "Science Direct" and "Interscience Wiley". The key words used were "mental retardation", "X chromosome", "gene", "syndromic mental retardation", "non-syndromic mental retardation".
Results:
In this review a number of X linked genes, the clinical features associated with the gene abnormality, and the prevalence of the disease gene are discussed. We classified these genes by order of their first implication in MR. A table presented on the XLMR Update Web site who list the 82 known XLMR genes is available as XLMR Genes and corresponding proteins.
Insights
This review synthesizes research on X-linked mental retardation (XLMR) genes, detailing their clinical features and prevalence. It highlights over 80 genes implicated in syndromic and non-syndromic forms of XLMR.
Area of Science:
- Genetics
- Neuroscience
- Medical Research
Background:
- Mental retardation (MR) affects 3% of the population and has over 900 genetic causes.
- X-linked mental retardation (XLMR) is categorized into syndromic (MRXS) and non-syndromic (MRX) forms.
- Fragile X syndrome is the most common syndromic XLMR.
Purpose of the Study:
- To systematically review and consolidate findings on X-linked mental retardation.
- To identify and discuss genes implicated in XLMR.
- To analyze clinical data and establish phenotype-genotype correlations for XLMR.
Main Methods:
- Conducted an exhaustive literature search using electronic and library resources.
- Utilized keywords such as 'mental retardation', 'X chromosome', and 'gene'.
- Focused on databases like 'Science Direct' and 'Interscience Wiley' for relevant studies.
Main Results:
- Discusses numerous X-linked genes associated with MR.
- Details clinical features linked to specific gene abnormalities and their prevalence.
- References a table listing 82 known XLMR genes and their corresponding proteins.
Conclusions:
- Provides a comprehensive overview of genes involved in X-linked mental retardation.
- Facilitates understanding of the genetic basis of XLMR.
- Supports further research into genotype-phenotype correlations for improved diagnosis and treatment.
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